03-23-2011
Quote:
Originally Posted by
sumoka
combining cat & Cut will cause spawning and will utilize more CPU threads which is fine for smaller files.
Not so much "fine" as "negligible".
Quote:
In case of bigger files as in my case, it is better to directly operate the Cut command on the file. This will result in optimum CPU utilization.
Correct. It's a bad habit in general -- test data tends to be small so the problem isn't apparent, only when you make it do real work will you run into trouble.
This User Gave Thanks to Corona688 For This Post:
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LEARN ABOUT OSF1
unix_master
unix_master(9r) unix_master(9r)
NAME
unix_master - General: Forces execution onto the master CPU
SYNOPSIS
void unix_master(
void );
ARGUMENTS
None
DESCRIPTION
The unix_master routine forces execution of the kernel thread onto the master CPU (also called the boot CPU). In other words, unix_master
binds the kernel thread to the master CPU. To release the kernel thread from the bind to the master CPU, call the unix_release routine. You
can make recursive calls to unix_master as long as you make an equal number of calls to unix_release.
The unix_master routine provides another way besides the simple and complex lock routines to make a kernel module symmetric multiprocessing
(SMP) safe. Although calling unix_master is not optimal for performance on an SMP CPU, it does provide third-party kernel module writers
with an easy way to make their modules SMP safe without using the lock routines.
NOTES
Device drivers should not directly call the unix_master and unix_release routines. One exception to this recommendation is when you want a
device driver's kernel threads to run only on the master CPU. This situation occurs when your driver creates and starts its own kernel
threads and you set the d_funnel member of the associated dsent structure to the value DEV_FUNNEL. In this case, each kernel thread must
call unix_master once to ensure that the kernel thread runs only on the master CPU. Remember to make a corresponding call to unix_release.
CAUTIONS
To avoid deadlock, do not call the unix_master routine under the following circumstances: When holding a simple lock In the driver's inter-
rupt service routine
RETURN VALUES
None
SEE ALSO
routines: unix_release(9r)
unix_master(9r)